In:
Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 95, No. 17 ( 1998-08-18), p. 10200-10205
Abstract:
Severe low-renin hypertension has few known causes. Apparent mineralocorticoid excess (AME) is a genetic disorder that results in severe juvenile low-renin hypertension, hyporeninemia, hypoaldosteronemia, hypokalemic alkalosis, low birth weight, failure to thrive, poor growth, and in many cases nephrocalcinosis. In 1995, it was shown that mutations in the gene ( HSD11B2 ) encoding the 11β-hydroxysteroid dehydrogenase type 2 enzyme (11β-HSD2) cause AME. Typical patients with AME have defective 11β-HSD2 activity, as evidenced by an abnormal ratio of cortisol to cortisone metabolites and by an exceedingly diminished ability to convert [11- 3 H]cortisol to cortisone. Recently, we have studied an unusual patient with mild low-renin hypertension and a homozygous mutation in the HSD11B2 gene. The patient came from an inbred Mennonite family, and though the mutation identified her as a patient with AME, she did not demonstrate the typical features of AME. Biochemical analysis in this patient revealed a moderately elevated cortisol to cortisone metabolite ratio. The conversion of cortisol to cortisone was 58% compared with 0–6% in typical patients with AME whereas the normal conversion is 90–95%. Molecular analysis of the HSD11B2 gene of this patient showed a homozygous C→T transition in the second nucleotide of codon 227, resulting in a substitution of proline with leucine (P227L). The parents and sibs were heterozygous for this mutation. In vitro expression studies showed an increase in the K m (300 nM) over normal (54 nM). Because ≈40% of patients with essential hypertension demonstrate low renin, we suggest that such patients should undergo genetic analysis of the HSD11B2 gene.
Type of Medium:
Online Resource
ISSN:
0027-8424
,
1091-6490
DOI:
10.1073/pnas.95.17.10200
Language:
English
Publisher:
Proceedings of the National Academy of Sciences
Publication Date:
1998
detail.hit.zdb_id:
209104-5
detail.hit.zdb_id:
1461794-8
SSG:
11
SSG:
12
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